1. Field of the Invention
The present invention relates to a light emitting diode (LED) lamp, and more particularly to a recessed LED lamp incorporating an improved heat sink for dissipating heat more efficiently and reducing a cost thereof.
2. Description of Related Art
As an energy-efficient light, an LED lamp has a trend of substituting the fluorescent lamp for indoor lighting purpose; in order to increase the overall lighting brightness, a plurality of LEDs are often incorporated into a signal lamp, in which how to efficiently dissipate heat generated by the LEDs becomes a challenge.
Conventionally, the LED lamp utilize a heat dissipating structure having a shape like a sunflower: a heat sink has a cylindrical post and a plurality of fins extending outwardly and radially from a circumference of the post. A bottom face of the post is used for thermally connecting with LEDs of the LED lamp. Thus, heat generated by the LEDs is conducted to the fins via the post, and dispersed to the surrounding environment from the fins.
Unfortunately, when such a conventional heat sink is used in the LED lamp, it cannot effectively dissipate heat generated by the LEDs since the LEDs act as multiple heat-generating centers, which require a heat sink with a large base to contact with the multiple heat-generating centers. However, the post of the sunflower-type heat sink cannot have a large base to contact with the LEDs due to the limitation of geometry of the cylindrical post. In addition, since in the sunflower-type heat sink, heat generated by the LEDs is firstly transferred vertically to the post and then horizontally to the fins via the post, the heat dissipating efficiency is not good enough to timely dissipate the heat generated by the LEDs.
Furthermore, the sunflower-type heat sink requires a high cost of manufacture.
What is needed, therefore, is an LED lamp with an improved heat sink which can overcome the above-mentioned disadvantages.